Which enemies can hurt me through walls?

Question

I am planning to set up an AFK farm for various rare enemy drops and coins. My plan is to wall myself into a room surrounded by lava pits and maybe some traps on timers. I plan to wear clorophyte armor and a star veil to gain some automated attacks.

I plan to set these up at various biomes and am interested in knowing what enemies will be able to attack me though the walls.

I know that wraiths, meteor eyes, worms type enemies, man eaters/snatchers, and a lot of the dungeon monsters can.

I can avoid wraiths by making my structure float. I am not concerned about meteor eyes as I already have everything I need from them. Worms do not do a lot of damage to me and I think I can kill them fairly quickly even while AFK. I do not plan to do this in the jungle much so the man eaters are also not a concern.

Answer 1

I have put enemies under specific lists based on how they pose a threat to your property.

Enemies of Property

• Zombies (come with demon eyes)

• Possessed Armor

• Goblin Sorcerer

• Wraiths

• Werewolfs

• Clown

• Eclipses

Can hit through Walls

• Goblin Sorcerer

• Wraiths

Damage Property

• Werewolves

Can enter home without doors

• Goblin Sorcerer

• Vampires

• Wraiths

Threats based on Time

Threats during Night

• Wraiths

• Possessed Armor

During Moons

• Werewolves (Full Moon)

• Clown (Blood Moon)

• Solar Eclipses

The following are strategies from the wiki I have put what threats will remain after you have completed the follow concepts.

Strategies

Digging a Deep Pit

Threats Left: Sorcerer, Demon Eye, Worms

A simple defense would be to dig a ditch underground that is too deep to jump out of, yet retains a way for a player to escape. A simple ditch would be dug out more than six blocks down, four blocks wide, with a ceiling of no more than four blocks high, while leaving a small area on the side of the pit opposite of your door so a player can jump up. If this is built properly, the only monsters capable of entering a house are the Sorcerer and the Demon Eye (most Goblins cannot enter because nobody can jump far enough with such a low ceiling). To remedy the Demon Eye problem, simply put a door on the other side of the ditch, as demonstrated on the left. Furthermore, if you dig a little farther until the Zombies can walk off screen, they will automatically despawn after enough time of being off screen, so the player doesn't have to worry about risking their life to kill a horde of Zombies.

Suspension House

Threats left: Flying Monsters, Sorcerer, Worms, Bosses

To counter flying monsters its recommended to use platform traps and doors.

Building a house in the air prevents any sort of land monster from entering the house regardless of their ability to knock down doors. Flying creatures can still be a problem but are easily nullified with platform traps and doors. Building a house like this is completely impenetrable except by Sorcerer, Worms, or bosses. As seen in the screenshot on the right, only one Zombie is allowed to spawn despite Blood Moon due to how many Demon Eyes are trapped. In addition, the player can fight on the ground with melee or from the central "airlock" of the house with ranged weapons. The only issue with this type of house is it can be detrimental to one's sense of gravity.

Advanced Approach

Threats Left: Demon Eyes

The major defense against basically all enemies is to have some type of block that stands out from all the others, and put it above the doors, then put at least three blocks of sand above it. One can now leave the door open almost 95% of time. Make sure that the door is opposite of where the sand is, otherwise the sand will just land on the door and sit there.

Sources

http://terraria.wikia.com/wiki/House_Defense

Answer 2

There are a number of enemies that can attack you through walls. They generally do so by either passing through the wall to make contact with you or by shooting a magical projectile at you that can go through walls.

Below is a list of monsters by biome that can attack you through walls. Biomes and monster names were taken from the Biomes article on the Terraria Wiki.

Surface & Underground themed biomes

Forest:

• Clown (explosive damage can penetrate wall, but not destroy them)
• Wraith

Ice:

• ice golem (not sure, maybe the lasers go through walls?)

Jungle:

• snatcher
• angry trapper

Corruption:

• Devourer
• world feeder
• clinger
• cursed hammer

Crimson:

• crimson axe
• floaty gross

Mushroom:

• fungi bulbs

Hallow:

• Wraith
• Rune Wizard
• enchanted sword
• chaos elemental (can teleport into houses)

Ocean: none

Desert: none

General Underground biomes

The underground:

• giant worm
• digger

The cavern:

• giant worm
• Tim
• digger
• rune wizard

The underworld:

• Fire imp
• bone serpent
• Demon (if walls are only 1 thick, their demon scythes can damage you )

Special biomes

Meteorite:

• meteor head

Floating island / high elevation:

• wyvern

Dungeon:

• any 'floating' monster
• most magic casting enemies